NetCat.ru is russian local company. “NetCat designed to create an absolute majority of the types of sites: from simple “business card" with a minimum content to complex web-based systems, from corporate offices to online stores, libraries or media data – in other words, projects completely different directions and at any level of complexity. View examples of sites running on NetCat CMS can be in a special section."

“Manage the site on the basis of NetCat can even inexperienced user, because it does not require knowledge of Internet technologies, programming and markup languages. NetCat constantly improving, adds new features. In the process of finalizing necessarily take into account the wishes of our partners and clients, as well as trends in Internet development. More than 2,000 studios and private web developers have chosen for their projects is NetCat, and in 2013 sites, successfully working on our CMS, created more than 18,000."

(2) Vulnerability Details:

NetCat web application has a computer security bug problem. It can be exploited by HTML Injection attacks. Hypertext Markup Language (HTML) injection, also sometimes referred to as virtual defacement, is an attack on a user made possible by an injection vulnerability in a web application. When an application does not properly handle user supplied data, an attacker can supply valid HTML, typically via a parameter value, and inject their own content into the page. This attack is typically used in conjunction with some form of social engineering, as the attack is exploiting a code-based vulnerability and a user’s trust.

Several NetCat products 0-day vulnerabilities have been found by some other bug hunter researchers before. NetCat has patched some of them. Web Security Watch is an aggregator of security reports coming from various sources. It aims to provide a single point of tracking for all publicly disclosed security issues that matter. “Its unique tagging system enables you to see a relevant set of tags associated with each security alert for a quick overview of the affected products. What’s more, you can now subscribe to an RSS feed containing the specific tags that you are interested in – you will then only receive alerts related to those tags." It has published suggestions, advisories, solutions details related to cyber security vulnerabilities.

“Facebook is an online social networking service headquartered in Menlo Park, California. Its website was launched on February 4, 2004, by Mark Zuckerberg with his college roommates and fellow Harvard University students Eduardo Saverin, Andrew McCollum, Dustin Moskovitz and Chris Hughes. The founders had initially limited the website’s membership to Harvard students, but later expanded it to colleges in the Boston area, the Ivy League, and Stanford University. It gradually added support for students at various other universities and later to high-school students. Since 2006, anyone who is at least 13 years old is allowed to become a registered user of the website, though the age requirement may be higher depending on applicable local laws. Its name comes from a colloquialism for the directory given to it by American universities students." (Wikipedia)

“Facebook had over 1.44 billion monthly active users as of March 2015.Because of the large volume of data users submit to the service, Facebook has come under scrutiny for their privacy policies. Facebook, Inc. held its initial public offering in February 2012 and began selling stock to the public three months later, reaching an original peak market capitalization of $104 billion. As of February 2015 Facebook reached a market capitalization of $212 Billion." (Wikipedia)

Facebook has a computer cyber security bug problem. It can be exploited by Open Redirect attacks. This could allow a user to create a specially crafted URL, that if clicked, would redirect a victim from the intended legitimate web site to an arbitrary web site of the attacker’s choosing. Such attacks are useful as the crafted URL initially appear to be a web page of a trusted site. This could be leveraged to direct an unsuspecting user to a web page containing attacks that target client side software such as a web browser or document rendering programs.

Since Facebook is trusted by large numbers of other websites. Those vulnerabilities can be used to do “Covert Redirect" to other websites such as Amazon, eBay, Go-daddy, Yahoo, 163, Mail.ru etc.

(1.1.1)

One Facebook Open Redirect vulnerability was reported to Facebook. Facebook adopted a new mechanism to patch it. Though the reported URL redirection vulnerabilities are patched. However, all old generated URLs are still vulnerable to the attacks. Section (2) gives detail of it.

The reason may be related to Facebook’s third-party interaction system or database management system or both. Another reason may be related to Facebook’s design for different kind of browsers.

(1.1.2) Another new Open Redirect vulnerability related to Facebook is introduced, too. For reference, please read section (3).

All URLs’ redirection are based on several files, such l.php, a.php, landing.php and so on.

The main redirection are based on file “l.php" (Almost all redirection links are using it right now).

For file “l.php", one parameter “h" is used for authentication. When it mentions to file “a.php", parameter “eid" is used for authentication. All those two files use parameter “u" for the url redirected to. In some other files such as “landing.php", parameters such as “url", “next" are used.

Those vulnerabilities were reported to Facebook in 2014 and they have been patched.

Several other similar products 0-day vulnerabilities have been found by some other bug hunter researchers before. Facebook has patched some of them. “The Full Disclosure mailing list is a public forum for detailed discussion of vulnerabilities and exploitation techniques, as well as tools, papers, news, and events of interest to the community. FD differs from other security lists in its open nature and support for researchers’ right to decide how to disclose their own discovered bugs. The full disclosure movement has been credited with forcing vendors to better secure their products and to publicly acknowledge and fix flaws rather than hide them. Vendor legal intimidation and censorship attempts are not tolerated here!" All the fllowing web securities have been published here, Buffer overflow, HTTP Response Splitting (CRLF), CMD Injection, SQL injection, Phishing, Cross-site scripting, CSRF, Cyber-attack, Unvalidated Redirects and Forwards, Information Leakage, Denial of Service, File Inclusion, Weak Encryption, Privilege Escalation, Directory Traversal, HTML Injection, Spam. Large number of Facebook bugs were published here. FD also publishes suggestions, advisories, solutions details related to Open Redirect vulnerabilities and cyber intelligence recommendations.

(4) Amazon Covert Redirect Security Vulnerability Based on Facebook

Since Facebook is trusted by large numbers of other websites. Those vulnerabilities can be used to do “Covert Redirect" to other websites such as Amazon.

“American electronic commerce company with headquarters in Seattle, Washington. It is the largest Internet-based retailer in the United States. Amazon.com started as an online bookstore, but soon diversified, selling DVDs, Blu-rays, CDs, video downloads/streaming, MP3 downloads/streaming, software, video games, electronics, apparel, furniture, food, toys and jewelry. The company also produces consumer electronics—notably, Amazon Kindle e-book readers, Fire tablets, Fire TV and Fire Phone — and is a major provider of cloud computing services. Amazon also sells certain low-end products like USB cables under its inhouse brand AmazonBasics. Amazon has separate retail websites for United States, United Kingdom & Ireland, France, Canada, Germany, The Netherlands, Italy, Spain, Australia, Brazil, Japan, China, India and Mexico. Amazon also offers international shipping to certain other countries for some of its products. In 2011, it had professed an intention to launch its websites in Poland and Sweden." (Wikipedia)

The vulnerability exists at “redirect.html?" page with “&location" parameter, e.g.

(4.1) When a user is redirected from Amazon to another site, Amazon will check parameters “&token". If the redirected URL’s domain is OK, Amazon will allow the reidrection.

However, if the URLs in a redirected domain have open URL redirection vulnerabilities themselves, a user could be redirected from Amazon to a vulnerable URL in that domain first and later be redirected from this vulnerable site to a malicious site. This is as if being redirected from Amazon directly.

“ESPN (originally an acronym for Entertainment and Sports Programming Network) is a U.S.-based global cable and satellite television channel that is owned by ESPN Inc., a joint venture between The Walt Disney Company (which operates the network, through its 80% controlling ownership interest) and Hearst Corporation (which holds the remaining 20% interest). The channel focuses on sports-related programming including live and recorded event telecasts, sports news and talk shows, and other original programming.

ESPN broadcasts primarily from studio facilities located in Bristol, Connecticut. The network also operates offices in Miami, New York City, Seattle, Charlotte, and Los Angeles. John Skipper currently serves as president of ESPN, a position he has held since January 1, 2012. While ESPN is one of the most successful sports networks, it has been subject to criticism, which includes accusations of biased coverage, conflict of interest, and controversies with individual broadcasters and analysts. ESPN headquarters in Bristol, Connecticut. As of February 2015, ESPN is available to approximately 94,396,000 paid television households (81.1% of households with at least one television set) in the United States. In addition to the flagship channel and its seven related channels in the United States, ESPN broadcasts in more than 200 countries, operating regional channels in Australia, Brazil, Latin America and the United Kingdom, and owning a 20% interest in The Sports Network (TSN) as well as its five sister networks and NHL Network in Canada."(Wikipedia)

Vulnerability description:

Espn.go.com has a cyber security bug problem. It is vulnerable to XSS (Cross Site Scripting) and Dest Redirect Privilege Escalation (Open Redirect) attacks.

Those vulnerabilities are very dangerous. Since they happen at ESPN’s “login" & “register" pages that are credible. Attackers can abuse those links to mislead ESPN’s users. The success rate of attacks may be high.

During the tests, besides the links given above, large number of ESPN’s links are vulnerable to those attacks.

“The Full Disclosure mailing list is a public forum for detailed discussion of vulnerabilities and exploitation techniques, as well as tools, papers, news, and events of interest to the community. FD differs from other security lists in its open nature and support for researchers’ right to decide how to disclose their own discovered bugs. The full disclosure movement has been credited with forcing vendors to better secure their products and to publicly acknowledge and fix flaws rather than hide them. Vendor legal intimidation and censorship attempts are not tolerated here!" A great many of the fllowing web securities have been published here, Injection, Broken Authentication and Session Management, Cross-Site Scripting (XSS), Insecure Direct Object References, Security Misconfiguration, Sensitive Data Exposure, Missing Function Level Access Control, Cross-Site Request Forgery (CSRF), Using Components with Known Vulnerabilities, Unvalidated Redirects and Forwards. It also publishes suggestions, advisories, solutions details related to XSS and Open Redirect vulnerabilities and cyber intelligence recommendations.

(1) XSS Web Security Vulnerability

XSS may allow a remote attacker to create a specially crafted request that would execute arbitrary script code in a user’s browser session within the trust relationship between their browser and the server. Base on Acunetix, exploited XSS is commonly used to achieve the following malicious results

From OWASP, an open redirect is an application that takes a parameter and redirects a user to the parameter value without any validation. This vulnerability is used in phishing attacks to get users to visit malicious sites without realizing it. This could allow a user to create a specially crafted URL, that if clicked, would redirect a victim from the intended legitimate web site to an arbitrary web site of the attacker’s choosing. Such attacks are useful as the crafted URL initially appear to be a web page of a trusted site. This could be leveraged to direct an unsuspecting user to a web page containing attacks that target client side software such as a web browser or document rendering programs.

A serious flaw in two widely used security standards could give anyone access to your account information at Google, Microsoft, Facebook, Twitter and many other online services. The flaw, dubbed “Covert Redirect" by its discoverer, exists in two open-source session-authorization protocols, OAuth 2.0 and OpenID.

Both standards are employed across the Internet to let users log into websites using their credentials from other sites, such as by logging into a Web forum using a Facebook or Twitter username and password instead of creating a new account just for that forum.

Attackers could exploit the flaw to disguise and launch phishing attempts from legitimate websites, said the flaw’s finder, Mathematics Ph.D. student Wang Jing of the Nanyang Technological University in Singapore.

Wang believes it’s unlikely that this flaw will be patched any time soon. He says neither the authentication companies (those with which users have an account, such as Google, Microsoft, Facebook, Twitter or LinkedIn, among others) nor the client companies (sites or apps whose users log in via an account from an authentication company) are taking responsibility for fixing the issue.

“The vulnerability is usually due to the existing weakness in the third-party websites," Wang writes on his own blog. “However, they have little incentive to fix the problem."

The biggest danger of Covert Redirect is that it could be used to conduct phishing attacks, in which cybercriminals seize login credentials, by using email messages containing links to malicious websites disguised as something their targets might want to visit.

Normal phishing attempts can be easy to spot, because the malicious page’s URL will usually be off by a couple of letters from that of the real site. The difference with Covert Redirect is that an attacker could use the real website instead by corrupting the site with a malicious login popup dialogue box.

For example, say you regularly visit a given forum (the client company), to which you log in using your credentials from Facebook (the authentication company). Facebook uses OAuth 2.0 to authenticate logins, so an attacker could put a corrupted Facebook login popup box on this forum.

If you sign in using that popup box, your Facebook data will be released to the attacker, not to the forum. This means the attacker could possibly gain access to your Facebook account, which he or she could use to spread more socially engineered attacks to your Facebook friends.

Covert Redirect could also be used in redirection attacks, which is when a link takes you to a different page than the one expected.

Wang told CNET authentication companies should create whitelists — pre-approved lists that block any not on it — of the client companies that are allowed to use OAuth and OpenID to redirect to them. But he said he had contacted a number of these authentication companies, who all shifted blame elsewhere.

Wang told CNET Facebook had told him it “understood the risks associated with OAuth 2.0″ but that fixing the flaw would be “something that can’t be accomplished in the short term." Google and LinkedIn allegedly told Wang they were looking into the issue, while Microsoft said the issue did not exist on its own sites.

Covert Redirect appears to exist in the implementations of the OpenID and OAuth standards used on client websites and apps. But because these two standards are open-source and were developed by a group of volunteers, there’s no company or dedicated team that could devote itself to fixing the issue.

Where does that leave things?

“Given the trust users put in Facebook and other major OAuth providers, I think it will be easy for attackers to trick people into giving some access to their personal information stored on those service," Chris Wysopal, chief technology officer of Boston-area security firm Veracode and a member of the legendary 1990s hackerspace the L0pht, told CNET.

“It’s not easy to fix, and any effective remedies would negatively impact the user experience," Jeremiah Grossman, founder of Santa Clara, Calif.-based WhiteHat Security, told CNET. “Just another example that Web security is fundamentally broken and the powers that be have little incentive to address the inherent flaws."

Users should be extra-wary of login popups on Web pages. If you wish to log into a given website, it might be better to use an account specific to that website instead of logging in with Facebook, Twitter, or another authentication company, which would require the use of OAuth and/or OpenID to do.

If you think someone has gained access to one of your online accounts, notify the service and change that account’s password immediately.